beautypg.com

Principle, Principle 2 – Bio-Rad Human MMP and TIMP Assays User Manual

Page 4

background image

Principle

Technology
The Bio-Plex

®

suspension array system is built upon the three core

elements of xMAP technology:

n

Fluorescently dyed microspheres (also called beads), each with a distinct

color code or spectral address to permit discrimination of individual tests
within a multiplex suspension. This allows simultaneous detection of more
than 100 different types of molecules in a single well of a 96-well microplate

n

A dedicated flow cytometer with two lasers and associated optics to

measure the different molecules bound to the surface of the beads. In
the Bio-Plex

®

MAGPIX

system, the sample is injected into a chamber

where the beads are imaged using LED and CCD technology

n

A high-speed digital signal processor that efficiently manages the

fluorescence data

Assay Format
Bio-Plex Pro

assays are essentially immunoassays formatted on

magnetic beads. The assay principle is similar to that of a sandwich
ELISA (Figure 1). Capture antibodies directed against the desired
biomarker are covalently coupled to the beads. Coupled beads react with
the sample containing the biomarker of interest. After a series of washes
to remove unbound protein, a biotinylated detection antibody is added
to create a sandwich complex. The final detection complex is formed
with the addition of streptavidin-phycoerythrin (streptavidin-PE or SA-PE)
conjugate. Phycoerythrin serves as a fluorescent indicator, or reporter.

2